It's high stakes for UK companies as sports betting starts to spread in America.

From Tuesday, new guidelines on betting came into result in Delaware, a tiny east coast state about 2 hours from Washington.

Neighbouring New Jersey might start accepting sports bets as early as Friday.

The changes are the very first in what could become a wave of legalisation after the Supreme Court last month cleared the way for states to permit sports wagering.

The industry sees a "once in a generation" opportunity to develop a new market in sports-mad America, said Dublin-based monetary expert David Jennings, who heads leisure research at Davy.

For UK companies, which are facing consolidation, increased online competitors and harder rules from UK regulators, the timing is especially suitable.

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But the industry says relying on the US remains a risky bet, as UK business face complex state-by-state policy and competitors from entrenched regional interests.

"It's something that we're actually focusing on, however equally we do not want to overhype it," stated James Midmer, representative at Paddy Power Betfair, which just recently acquired the US fantasy sports betting site FanDuel.

'Take some time'

The US represented about 23% of the world's $244bn (₤ 182bn) in video gaming earnings last year, according to a report by Technavio, external published in January.

Firms are hoping to tap into more of that activity after last month's decision, which overruled a 1992 federal law that disallowed states outside of Nevada and a few others from authorising sports wagering.

The ruling discovered the law was an over-reach of federal power. But the court it did not in fact legalise sports betting wagering, leaving that question to regional legislators.

That is anticipated to result in significant variation in how firms get licensed, where sports betting can take place, and which occasions are open to speculation - with huge implications for the size of the market.

Potential profits varieties from $4.2 bn to nearly $20bn annually depending on aspects like the number of states relocate to legalise, Oxford Economics approximated in a 2017 research study for the American Gaming Association.

"There was a great deal of 'this is going to be substantial'", stated Will Hawkley, London-based head of leisure for consultants KPMG.

Now, he said: "I think many people ... are looking at this as, 'it's an opportunity but it's not going to be $20bn and it's going to be state by state and it's going to require time'."

'Remains to be seen"

Chris Grove, handling director at Eilers & Krejcik Gaming, forecasts that 32 states will legalise sports wagering in some kind by 2023, creating a market with about $6bn in yearly profits.

But bookmakers face a far different landscape in America than they do in the UK, where betting stores are a regular sight.

US laws restricted gaming mainly to Native American lands and Nevada's Las Vegas strip up until fairly recently.

In the popular imagination, sports betting wagering has actually long been linked to a 1919 baseball World Series match-fixing scandal.

States have also been sluggish to legalise numerous kinds of online gambling, in spite of a 2011 Justice Department viewpoint that appeared to get rid of challenges.

While sports betting is usually viewed in its own classification, "it clearly remains to be seen whether it gets the sort of momentum people think it will," stated Keith Miller, law teacher at Drake University and co-author of a book about sports wagering policy.

David Carruthers is the former president of BetonSports, who was arrested in the US in 2006 for running an overseas online sportsbook and served jail time.

Now an expert, he says UK firms ought to approach the marketplace carefully, selecting partners with caution and avoiding missteps that might cause regulator reaction.

"This is a chance for the American sports wagerer ... I'm not exactly sure whether it is a chance for service," he states. "It truly depends on the outcome of [state] legislation and how business operators pursue the chance."

'It will be partnerships'

As legalisation starts, sports betting wagering companies are lobbying to fend off high tax rates, in addition to requests by US sports leagues, which desire to gather a portion of earnings as an "integrity cost".

International companies face the added difficulty of a powerful existing gaming industry, with gambling establishment operators, state-run lottery games and Native American tribes that are looking for to defend their turf.

Analysts state UK companies will need to strike collaborations, providing their competence and technology in order to make inroads.

They indicate SBTech's recent announcement that it is supplying innovation for Kentucky Derby operator Churchill Downs as an example of the type of deals likely to materialise.

"It will be a win-win for everyone, but it will be collaborations and it will be driven by technology," Mr Hawkley stated.

'It will simply depend'

Joe Asher, president at William Hill US, is clear-eyed about the truths.

The company has been buying the US market considering that 2011, when it purchased three US companies to establish a presence in Nevada.

William Hill now uses about 450 individuals in the US and has revealed partnerships with gambling establishments in Iowa and New Jersey.

It works as threat supervisor for the Delaware Lottery and has invested millions alongside a local developer in a New Jersey horse racing track.

Mr Asher stated William Hill has actually become a household name in Nevada however that's not necessarily the goal all over.

"We certainly plan to have a really considerable brand presence in New Jersey," he stated. "In other states, it will simply depend on regulation and possibly who our regional partner is."

"The US is going to be the most significant sports betting wagering market worldwide," he added. "Obviously that's not going to occur on day one."